1. Field of the Invention
The invention generally relates to a system for providing improved fuel in a more efficient manner to an internal combustion engine. More specifically, the invention involves the field of technology relating to hydrocarbon fuel treatment or modification systems that are utilized in conjunction with internal combustion engines, particularly those associated with vehicles.
2. Description of the Prior Art
Internal combustion engines are generally fueled by hydrocarbon fuel sources, such as kerosene, gasoline and the like. In particular, the current use of gasoline by such engines does involve many engineering considerations if the problems attendant the use of this fuel are to be minimized. In addition to such considerations, there is also the realization that the world oil supply is substantially finite, thereby imposing increased financial and source material constraints as the demand for gasoline increases with the passing years.
Current internal combustion engines fueled by gasoline are generally inefficient and produce various emissions or products of combustion which have harmful effects on the general environment. Moreover, such engines operate at rather high temperatures which often cause breakdowns of lubricating oils, degradation of sparkplugs, valves and other engine components, and production of undesirable carbonaceous deposits on the engine working surfaces which reduce engine life and increase maintenance costs.
A given volume of gasoline is substantially comprised of two-thirds by volume of lighter fractions which as a gas are paraffinic in nature and one-third by volume heavier fractions which are oily in nature. During the operation of a vehicle engine, gasoline droplets mixed with air from the carburetor are introduced into the heated intake manifold and respective hot combustion chambers wherein there occurs a separation of lighter fractions from the heavier fractions and also some conversion of the hydrocarbons into various petrochemical products due to the liquid phase oxidation of the hydrocarbons. The combustion of the air and the lighter hydrocarbon fractions is inhibited by the presence of the heavier hydrocarbon fractions, trace petrochemicals and certain gasoline additives present. This situation encumbers ignition of lean fuel mixtures having higher than stoichiometric air-to-fuel ratios. Moreover, such mixtures are slow burning and require ignition before the engine reaches top dead center, particularly in short stroke engines, thereby reducing engine efficiency. The efficiency of an engine is further reduced by creating rich fuel mixtures having lower than stoichiometric air-to-fuel ratios by normal operational procedures, such as choking, idling and accelerating.
When gasoline undergoes combustion in an engine, a rich fuel mixture having a lower than stoichiometric air-to-fuel ratio generally yields carbon monoxide, unburned hydrocarbons and causes the engine to operate at a fairly high temperature. A stoichiometric fuel mixture having an ideal air-to-fuel ratio will generally yield nitrous oxides and produce an excessively hot engine. However, an engine that is operated with a lean fuel mixture having a higher than stoichiometric air-to-fuel ratio produces a minimum of harmful emissions or products of combustion. This latter situation permits the engine to operate at the coolest possible temperature in very high air-to-fuel ratios. In order to realize this desirable objective, it has been recognized that a lean fuel mixture cannot be utilized unless the fuel itself is more volatile than gasoline so that ignition can readily occur at high air-to-fuel ratios. With such a volatile fuel, substantially complete combustion is achieved, with a minimum production of undesirable products of combustion. Correspondingly lower engine operating temperatures are realized, as well as increased fuel efficiency. The lighter hydrocarbon fractions in gasoline are characteristic of such volatile fuels.
The prior art has recognized that the lighter fractions of hydrocarbon fuels, particularly gasoline, do provide enhanced operating characteristics when utilized for the initial starting of internal combustion engines, particularly in cold weather. This is due to the high volatility of the lighter fractions which, during engine start-up, permit faster engine starting due to more rapid vaporization of such volatile fuel in the induction system of the engine. It has also been recognized that such fuels serve to reduce cold start exhaust emissions when compared to the use of regular fuel, such as gasoline. The prior art practice has been limited to the use of the lighter fractions of gasoline, generally referred to as dry gas, as a specialized fuel limited only for engine starting. It has been maintained that the continued use of such a high volatility fuel in the engine after engine warm-up is not practical due to economic considerations, with the use of regular gasoline in a conventional fuel system being preferred for continued engine operation. Accordingly, it has heretofore been necessary to incorporate dual fuel systems wherein the high volatile fractions are utilized only for engine start-up and a conventional fuel is used for the continued operation of the engine. It has further been proposed to utilize only one source of starting fuel in conjunction with the operation of an engine wherein the fuel source is treated to extract lighter fractions therefrom for providing engine starting fuel.